January 21, 2009

MOA-192 b still at 3.3 Earth Masses

Bummer. There was an error.
The flood of news reporting that the mass of exoplanet MOA-2007-BLG-192L b (MOA-192 b) was revised to 1.5 or 1.4 Earth masses was an error.
Officially, the correct mass of MOA-192 b is still 3.3 Earth masses, and NOT 1.5 Earth masses as reported in the news yesterday.
Lest I myself err in that regard, I am posting the exact message today from David Bennett who wrote to the exoplanet mailing list I am subscribed to.

"The New Scientist and perhaps other media outlets are reporting that the mass of MOA-2007-BLG-192Lb has been revised down to 1.5 Earth masses, but these reports are in error. The reporter has been confused by a report of one of my colleagues regarding a revision in the mass estimate that would be possible if the host star was confirmed to be a ~0.09 solar mass M-dwarf instead of a brown dwarf. The correct mass estimate remains 3.3 (+4.9 / - 1.8) Earth masses. This is currently the lowest mass estimate for an exoplanet except for PSR 1257+12 b, but the error bars have large overlap with a number of other planets detected by both radial velocities and microlensing." - David Bennett, for the MOA, OGLE, and PLANET collaborations

Thus, MOA-2007-BLG-192L b remains as a Super-earth. And Earth-like Worlds remain elusive. But with the launch of Kepler this coming March 2009, true Earth-like worlds will even come closer to being discovered.
I can hardly wait.